Propanediamine and alkylated iminobispropylamines such as methyliminobispropylamines are known compositions and have been used in the manufacture of chelating agents and in paper applications as a wet end additive.
The following patents are representative of various processes to produce aliphatic and cyclic polyamines:
U.S. Pat. No. 2,452,602 discloses a process for producing aliphatic polyamines by reacting an unsaturated aldehyde with ammonia in the presence of hydrogen. In this reaction, a conventional hydrogenation catalyst, e.g., Raney nickel catalyst, is used to enhance the condensation of the aldehyde with ammonia to produce the aliphatic amine. A specific example shows the production of n-butylamine by reaction of crotonaldehyde with ammonia in the presence of hydrogen.
U.S. Pat. No. 2,349,461 discloses procedures for producing secondary and tertiary amines by reacting an aldehyde or ketone with ammonia in the presence of hydrogen and a hydrogenation catalyst and by reducing alkylcyanides with hydrogen in the presence of hydrogenation catalyst. To produce secondary or tertiary amines the patentees react hydrogen at an elevated temperature with a mixture containing a nitrile, alcohol, aldehyde or ketone in the presence of a hydrogenation catalyst. Diethylamine is prepared by reacting acetonitrile with acetaldehyde in the presence of hydrogen.
U.S. Pat. No. 3,522,309 discloses a process for the reductive alkylation of amines to produce N-alkylated amines. In this process, ammonia or primary and secondary amines are contacted with a carbonyl compound, e.g., an aldehyde, in the presence of a hydrogenation catalyst, e.g., a platinum or palladium metal on a support.
U.S. Pat. No. 3,119,872 discloses a process for producing aliphatic 1,3-diamines by reacting an alpha-beta-unsaturated aldehyde or ketone with ammonia or primary amine and then catalytically hydrogenating the condensation product.
U.S. Pat. No. 2,579,580 discloses the cyanoethylation of organic compounds containing labile hydrogen atoms, such as amines, amides, and ketones. The cyanoethylation reaction is carried out in the presence of a cross-linked polyquaternary ammonium hydroxide resin.
U.S. Pat. No. 2,045,574 discloses the process for producing amines by contacting a carbonyl compound with ammonia or an amine with hydrogen in the presence of a hydrogenation catalyst.
Re. No. 23,124 discloses the process of producing N-dimethylethanolamines by alkylating cyanhydrins. The alkylation is effected by contacting the cyanhydrin with an aldehyde in the presence of hydrogen and a hydrogenation catalyst, e.g., a nickel, cobalt or nickel-cobalt catalyst system.
It is also know from the prior art that 1,3-propanediamine can be prepared by cyanoethylation of ammonia followed by catalytic hydrogenation of the resulting nitrile. This reaction typically results in the production of a by-product, namely, iminobispropionitrile. This is due to the inherent over-cyanoethylation of ammonia which then on hydrogenation forms iminobispropylamine. Alkylation of the iminobispropylamine results in a variety of by-products.